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1.
一种改进的HMRSVP方案   总被引:4,自引:0,他引:4  
介绍了RSVP与MRSVP,以及在Mobile IP中采用MRSVP实现QoS保障的机制。分析和比较了3种HMRSVP方案,特别是指针转发的HMRSVP方案,并提出一种改进的方案。在此方案中,若移动主机在同一个分层区域内移动,则利用它在移动时所具有的本地性,采用指针转发的HMRSVP方案;若移动主机进入新的分层区域,则要求它建立新的RSVP通路,开始新的指针转发过程。同时对本地化特性进行了讨论。对改进的方案在两种情况下分别进行了建模、分析、结果表明,改进的方案性能更加优越。  相似文献   

2.
移动IP技术能够支持基于IP的无线网络,资源预留协议(RSVP)用来保证多媒体传输的服务质量。然而把现有的RSVP应用于移动IP网络就会存在许多问题。提出了一种改进的RSVP支持方案(ERSVP)来实现无线IP网络的服务质量保证。ERSVP在分层网络中结合了MRSVP和RSVP隧道技术。根据性能分析,ERSVP方案能够获得比MRSVP较少的信令延迟、信令负载和资源耗费。  相似文献   

3.
刘星沙  彭浩  严旭影 《信息技术》2007,31(8):127-129,158
资源预留协议RSVP能够为用户提供端到端的传输带宽。为保证在移动IP下的服务质量,针对RSVP协议提出很多改进方案,如隧道RSVP,MRSVP和HMRSVP等。对宏移动和微移动下的RSVP扩展方案进行了讨论,最后提出进一步的研究方向。  相似文献   

4.
This paper describes a reservation protocol to provide real-time services to mobile users in an Integrated Services Packet Network. Mobility of hosts has significant impact on the quality of service provided to a real-time application. The currently proposed network system architecture and mechanisms to provide real-time services to fixed hosts are inadequate to accommodate the mobile hosts which can frequently change their point of attachments to the fixed network. Mobile hosts may experience wide variations of quality of service due to mobility. To reduce the impacts of mobility on QoS guarantees, a mobile host needs to make advance resource reservations at multiple locations it may possibly visit during the lifetime of the connection. The currently proposed reservation protocol in the Internet, RSVP, is not adequate to make such reservations for mobile hosts. In this paper, we describe a new reservation protocol, MRSVP, for supporting integrated services in a network with mobile hosts.  相似文献   

5.
In recent years, with the development of mobile communication technologies and the increase of available wireless transmission bandwidth, deploying multimedia services in next generation mobile IPv6 networks has become an inevitable trend. RSVP (resource reservation protocol) proposed by the IETF is designed for hardwired and fixed networks and can not be used in mobile environments. This paper proposes a protocol, called Fast RSVP, to reserve resources for mobile IPv6. The protocol adopts a cross-layer design approach where two modules (RSVP module and Mobile IPv6 module) at different layers cooperate with each other. Fast RSVP divides a handover process with QoS guarantees into two stages: (1) setup of the resource reservation neighbor tunnel and (2) resource reservation on the optimized route. It can help a mobile node realize fast handover with QoS guarantees as well as avoid resource wasting by triangular routes, advanced reservations and duplicate reservations. In addition, fast RSVP reserves “guard channels” for handover sessions, thus greatly reducing the handover session forced termination rate while maintaining high performance of the network. Based on extensive performance analysis and simulations, Fast RSVP, compared with existing methods of resource reservation in mobile environments, performs better in terms of packet delay and throughput during handover, QoS recovery time after handover, resource reservation cost, handover session forced termination rate and overall session completion rate.  相似文献   

6.
RSVP: a new resource ReSerVation Protocol   总被引:4,自引:0,他引:4  
A resource reservation protocol (RSVP), a flexible and scalable receiver-oriented simplex protocol, is described. RSVP provides receiver-initiated reservations to accommodate heterogeneity among receivers as well as dynamic membership changes; separates the filters from the reservation, thus allowing channel changing behavior; supports a dynamic and robust multipoint-to-multipoint communication model by taking a soft-state approach in maintaining resource reservations; and decouples the reservation and routing functions. A simple network configuration with five hosts connected by seven point-to-point links and three switches is presented to illustrate how RSVP works. Related work and unresolved issues are discussed  相似文献   

7.
While the Internet keeps its penetration into every facet of life and every corner of the globe, two things stand out. One is the hunger for high quality of services to convey audio and video data. The other is the desire for ubiquitous connections. Combining the two we have an Internet that is capable of supporting multimedia communications for nomadic users on the move. To have a high quality connection, resource must be allocated along the connection path. The current Internet standard for resource reservation is RSVP (Resource reSerVation Protocol), which is receiver-initiated and allows one-to-one or one-to-many communication to have resource reserved in the path from sender to receiver(s). To support mobile users, the Internet also has the mobile IP standard. Mobile IP allows a mobile host to roam from one subnet to another seamlessly. However, several problems need to be solved before we can support QoS communications for mobile users by applying RSVP to mobile IP. In this paper, we identify four problems related to RSVP over mobile IP. The problems are the resource pre-reservation problem, the RSVP tunneling problem, the common path identification problem, and the mobile proxy problem. We also survey the various solutions proposed by many papers.  相似文献   

8.
Quality-of-service mechanisms in all-IP wireless access networks   总被引:7,自引:0,他引:7  
In this paper, we focus on resource reservation protocol (RSVP)-based quality-of-service (QoS) provisioning schemes under Internet protocol (IP) micromobility. We consider QoS provisioning mechanisms for on-going RSVP flows during handoff. First, the rerouting of RSVP branch path at a crossover router (CR) at every handoff event can minimize resource reservation delays and signaling overheads, and in turn the handoff service degradation can be minimized. We show that RSVP branch path rerouting scheme could give a good tradeoff between the resource reservation cost and the link usage. Second, the new RSVP reservation can be made along the branch path toward the CR via a new base station in advance, while the existing reservation path is maintained, and in turn the on-going flow can be kept with the guaranteed QoS. We also show that seamless switching of RSVP branch path could provide the QoS guarantee by adaptively adjusting the pilot signal threshold values. Third, during RSVP resource reservation over wireless link, dynamic resource allocation scheme is used to give a statistical guarantee on the handoff success of on-going flows. We finally obtain the forced termination probability of guaranteed service flows, the average system time of best effort flows by using a transition rate matrix approach.  相似文献   

9.
RSVP Extensions for Real-Time Services in Hierarchical Mobile IPv6   总被引:2,自引:0,他引:2  
The Mobile IPv6 (MIPv6) provides many great features, such as sufficient addressing space, mobility, and security; MIPv6 is one of the most important protocols for next generation mobile Internet. Simultaneously, with the rapid improvement of wireless technologies, the real-time multi-media IP services such as video on demand, videoconference, interactive games, IP telephony and video IP phone will be delivered in the near future. Thus, to furnish accurate QoS for real-time services is one of the most important thing in the next generation mobile Internet. Although RSVP, which is a resource reservation protocol, processes signaling messages to establish QoS paths between senders and receivers, RSVP was originally designed for stationary networks and not aware of the mobility of MNs. Therefore, this paper proposes a novel RSVP extension to support real-time services in Hierarchical Mobile IPv6 (HMIPv6) environments. For intra-site mobility, the concept of QoS Agent (QA) is proposed to handle the RSVP QoS update messages and provide the advanced reservation models for real-time services. For inter-site mobility, IP multicast can help to invite inter-site QAs to make pre-reservation and minimize the service disruption caused by re-routing the data path during handover. Simulation results show that the proposed scheme over HMIPv6 is more suitable for real-time services than the famous RSVP tunnel-based solution.  相似文献   

10.
基于移动Agent技术的QoS保障机制   总被引:1,自引:0,他引:1  
介绍了移动Agent的基本特性。移动Agent可在异构的网络各个节点间自由地移动,它能感知网络的状态,监控系统并与其他Agent进行交互。IETF的IS模型采用了RSVP(ResourcereSerVationProtocol)协议对系统资源进行预留,从而达到一定程度上保障所需QoS的目的。QoS保障机制将移动agent技术与RSVP协议结合起来,通过资源预留和agent动态移动的实现可以达到更好地改善QoS的目的。  相似文献   

11.
A crucial component of the interaction between ATM's and the Internet's Quality of Service (QoS) architectures is the efficient mapping of RSVP (Resource reSerVation Protocol) as the Internet's signalling protocol onto the according ATM mechanisms. In particular, this article focuses on one of the most contrary characteristics of RSVP and ATM signalling. This is the support for heterogeneous reservations by RSVP over the ATM subnetwork, taking into account that ATM only allows for a homogeneous QoS within a single Virtual Circuit (VC). We present previous approaches to the solution of this problem and argue for more sophisticated and efficient approaches to manage ATM VCs taking into consideration ATM tariffs and resource consumption.  相似文献   

12.
We propose a pointer forwarding scheme for the mobile resource reservation protocol (MRSVP) to reduce the resource reservation cost on the wireless Internet. We show that the pointer forwarding scheme could significantly degrade the reservation cost when a mobile host performs locality movement  相似文献   

13.
Wavelength‐routed Generalized Multi‐Protocol Label Switching (GMPLS) networks use Resource reSerVation Protocol—Traffic Engineering (RSVP‐TE) as signaling protocol to set up and tear down lightpaths. RSVP‐TE uses a soft‐state control mechanism to manage lightpaths. In the soft‐state control mechanism, each node sets a timer for each control state and resets the timer with refresh messages to maintain the state. When the timer expires due to losses of refresh messages, the control state is initialized and a reserved resource managed with the state is released. It has been considered that resource utilization of soft‐state protocols is inferior to that of hard‐state protocols, since soft‐state protocols may reserve resources until control states are deleted due to timeout. Therefore, some extensions to promote the performance of soft‐state protocols, such as message retransmission, have been considered. In this paper, we analyze the behavior of GMPLS RSVP‐TE and its variants with a Markov model and analyze the performance of RSVP‐TE. From the results, we demonstrate that resource utilization of RSVP‐TE can be equivalent to that of a hard‐state protocol when the loss probability of signaling messages is low. We also investigate the effectiveness of message retransmission and show that using message retransmission leads to poor resource utilization in some cases. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

14.
本文主要针对基于RSVP的保证服务,讨论了如何利用非线性服务曲线进行资源分配,以实现带宽和时延要求的解耦。提出了一种简单有效的非线性服务曲线,数值分析结果表明就资源利用率而言,其性能远远优于传统的线性服务曲线。最后论文讨论了未来的发展趋势并给出了有待研究的一些课题。  相似文献   

15.
One of the major problems of deploying Resource ReSerVation Protocol (RSVP) in mobile environments is called the advance resource reservation (ARR) problem. Conventional solutions to this problem waste too many network resources and increase the new Quality of Service (QoS) session blocking probability. In this paper, we propose a reservation optimised ARR scheme which constrains the number of advance reservation paths in a subnet and only allows the most eligible mobile nodes to make advance reservations. Furthermore, to evaluate the performance of the schemes, we build Markovian models of different ARR schemes using a formal performance modelling formalism named Performance Evaluation Process Algebra (PEPA). Our results indicate that the proposed reservation optimised ARR scheme can effectively balance the active and passive reservation blocking probabilities and achieves a better utilisation of the network resources, especially when the traffic intensity is high.  相似文献   

16.
1IntroductionMobile users want to enjoy multi media and other real-ti me services in the Internet . Thus the Internet Engi-neering Task Force (IETF) has introduced the MobileIPv4[1]and Mobile IPv6[2]to interoperate seamlesslywith protocols that provide real-ti me services in the In-ternet. Multi-Protocol Label Switching ( MPLS) is afast label-based switching technology that integrates thelabel-swapping paradigm with network-layer routing[3].Resource Reservation Protocol ( RSVP)[4 ~…  相似文献   

17.
The coupling of signaling protocols for mobility management and resource reservation plays an important role to achieve Quality-of-Service (QoS) in wireless environments. When performing a handover, request and allocation of resources have to be done in the shortest possible time to avoid disruptions for the user service. Therefore, it is preferable to ensure resource availability in advance, which we call anticipated handover. This approach for providing seamless handovers in turn poses challenges for the overall design of the QoS architecture and its associated QoS signaling protocol. This article describes the design, implementation, and evaluation of a comprehensive QoS architecture and a suitable QoS signaling protocol. It discusses intrinsic problems of reservations in IP based networks such as session ownership as well as a number of protocol design issues regarding the integration of QoS signaling with other protocols, such as Mobile IP. In particular, we define an end-to-end QoS architecture and a mobility-aware reservation signaling protocol Mobility Aware Reservation Signaling Protocol (MARSP) that supports anticipated handover, thus enabling seamless services over heterogeneous wireless access networks. The presented architecture and protocol were implemented and evaluated by measurements. They show that anticipated handovers not only outperform hard handovers regarding handover latency, but that they also provide functional and robustness advantages. Authors Hillebrand and Prehofer changed their affiliation in the meantime, the work described in this paper was carried out during their employment at DoCoMo Communications Laboratories Europe.  相似文献   

18.
Resource reservation protocol (RSVP) is a network‐control protocol used to guarantee Quality‐of‐Service (QoS) requirements for real‐time applications such as Voice‐over‐IP (VoIP) or Video‐over‐IP (VIP). However, RSVP was designed for end‐systems whose IP addresses do not change. Once mobility of an end‐system is allowed, the dynamically changing mobile IP address inevitably impacts on RSVP performance. Our study aims to first quantify the significance of this impact, and then propose a modified RSVP mechanism that provides improved performance during handoffs. Our simulations reveal that the deployment of standard RSVP over Mobile IPv6 (MIPv6) does not yield a satisfactory result, particularly in the case of VIP traffic. Fast Handovers for Mobile IPv6 (FMIPv6) was found to be providing the best performance in all tested scenarios, followed by Hierarchical Mobile IPv6 (HMIPv6) with a single exception: during low handoff rates with VoIP traffic, MIPv6 outperformed HMIPv6. We then designed a new RSVP mechanism, and tested it against standard RSVP. We found that the proposed approach provides a significant improvement of 54.1% in the Total Interruption in QoS (TIQoS) when deployed over a MIPv6 wireless network. For HMIPv6, performance depended primarily on the number of hierarchical levels in the network, with no improvement in TIQoS for single‐level hierarchy and up to 37% for a 5‐level hierarchy. FMIPv6 on the other hand, provided no room for improvement due to pre‐handoff signaling and the tunneling mechanism used to ensure a mobile node (MN)'s connectivity during a handoff, regardless of the RSVP mechanism used. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

19.
Braun  R. 《Multimedia, IEEE》1997,4(4):74-82
Part I (ibid., July-Oct. 1997) surveyed the evolution of Internet protocols and applications and described the Internet protocol IPv6 in detail. This part discusses new developments at the upper layers that support real-time Internet multimedia, such as audio and video conferencing and shared whiteboard applications. Application-level framing (ALF), proposed in 1990 for protocol and application design, now forms the basis for many new Internet protocols and applications, including Real-time Transport Protocol (RTP) and Mbone multimedia applications. RTP supports real-time applications that adapt to changing network situations to maintain the quality of service (QoS). The Resource Reservation Protocol (RSVP) provides new Internet services with higher quality than best-effort by means of resource reservations  相似文献   

20.
Dynamic RSVP protocol   总被引:5,自引:0,他引:5  
RSVP is a resource reservation setup protocol that can be used by a host to request specific QoS for multicast multimedia flows on the Internet. Multiprotocol label switching (MPLS) architecture also needs RSVP. The fact that the resolutions of the display system used in different receiver nodes might have different, multi-resolution characteristics is supported in the MPEG-4 standard, and the EZW compression algorithm can cease decoding at any point in the bitstream. However, RSVP does not provide a more flexible mechanism. In this article we propose an extension of RSVP to provide the needed mechanism, coined dynamic RSVP (DRSVP), to dynamically adjust reserved resources on nodes without much effort. It provides different video resolutions to different receiver nodes with different needed reserved resources. Therefore, it does not waste precious Internet resources to transmit unnecessary multimedia packets.  相似文献   

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